Short answer: no. Google’s own Search guidance lists llms.txt among the things you do NOT need for AI search features. If someone tries to sell you one this month, you can skip it.
Here’s why you’re about to hear about it anyway. Google’s Chrome team just published an llms.txt page under an experimental Lighthouse audit category called Agentic Browsing. Within a day, SEO Twitter was framing it as “Google officially endorses llms.txt.” It doesn’t. The audit is labeled experimental, and if your site doesn’t have the file, Lighthouse marks it “Not Applicable.” Not a fail. Not a penalty. Nothing.
Meanwhile Google has called llms.txt “purely speculative for now” when asked about Search. Both of those statements come from Google. One is a developer experiment, the other is the search team telling you it doesn’t matter yet. Guess which one the sales pitches will quote.
I get why this stuff works on business owners. You’re slammed, AI search is new and confusing, and a vendor with a checklist sounds like a safe way to not fall behind. But I look at what AI search actually pulls from when I check it for a roofing client here in San Antonio, and it’s never some special file on their website. The answers come from reviews across multiple platforms, “best roofer in [city]” lists, and pages that answer the exact question someone asked. Ahrefs ran the numbers on over a billion data points and found the same thing: third-party mentions and listicles drive AI citations. A site summary file doesn’t move the needle.
For what it’s worth, llms.txt is harmless. It’s a markdown summary of your site that costs almost nothing to add, and we’ll add one for clients as a nice-to-have. The problem isn’t the file. The problem is paying “AI SEO” money for it while your review count and your citations, the things AI actually reads, sit untouched.
If a vendor pitches you an llms.txt package, ask them one question: why does Google’s own testing tool treat it as optional? Then spend the money asking five happy customers for a review instead.
Good Company AI helps local businesses in San Antonio and South Texas get found, get trusted, and get more calls from Google. If you want to know exactly where your business stands in AI search and what actually moves the needle, request a free visibility audit and we’ll show you.